mercruiser 470 putters at half throtle, idles fine

[robbie419toledo]

my boat starts fine but when I give it some gas the motor runs rough. It idles perfect but when I get to about 2300 RPMs it stutters . This began 30 minutes after I hit a sand bar. It did fine for 30 minutes it planed out despite a slightly damaged prop . Then it slowed down and now I can only go at a slow speed . Could this be a timing issue ? I changed the fuel filters (2 in-line and carb). Is there one in the fuel pump? Its an 83 the points , condenser, cap, rotor , wires plugs are good . Carb and gasket seems OK. I just had the engine out to replace the coupler . I put it in the water and it ran perfect for 30 minutes then i hit a sand bar ; after that there was a slight vibration from prop damage. The prop was replaced . It still runs crappy. thanks in advance!

 

[ErieRon]

Re: mercruiser 470 putters at half throtle, idles fine

My 470 has a filter in the fuel pump. The pump is a bayonet style. The original filter was a ceramic bowl, but has since been replaced by a paper cartridge type. Just make sure you install it with the open end of the filter facing down in the bowl.

Sorry I can't help with the rest...watch those sand bars!